How do I paint over backer board designed for water areas?

Question

Failed wall application on a remodeled master bath. Remodel about 3 years ago. Plaster and paint crumbling off walls. In some places no plaster just old paint. Under the old paint where there is no plaster looks like drywall designed for water areas, there is no paper over it like traditional drywall but a heavy coating. Can I just paint over it?????

Kelli L. Milligan · Answer

Can you attach pictures. I can't figure out what you are describing. Sounds like you may have to remove whatever you have.

Kathy Gunter Law · Answer

You should smooth it out with dry wall mud then use a damp sponge. It may take a few applications before it has a nice appearance. Once it's fully cured, then you can prime and paint.